; standard driver stuff; version of driver model = 5 format PE DLL native 0.05 entry START DEBUG = 1 DUMP_PACKETS = 0 ; this is for DEBUGF macro from 'fdo.inc' __DEBUG__ = 1 __DEBUG_LEVEL__ = 1 include '../struct.inc' ; USB constants DEVICE_DESCR_TYPE = 1 CONFIG_DESCR_TYPE = 2 STRING_DESCR_TYPE = 3 INTERFACE_DESCR_TYPE = 4 ENDPOINT_DESCR_TYPE = 5 DEVICE_QUALIFIER_DESCR_TYPE = 6 CONTROL_PIPE = 0 ISOCHRONOUS_PIPE = 1 BULK_PIPE = 2 INTERRUPT_PIPE = 3 ; USB structures struct config_descr bLength db ? bDescriptorType db ? wTotalLength dw ? bNumInterfaces db ? bConfigurationValue db ? iConfiguration db ? bmAttributes db ? bMaxPower db ? ends struct interface_descr bLength db ? bDescriptorType db ? bInterfaceNumber db ? bAlternateSetting db ? bNumEndpoints db ? bInterfaceClass db ? bInterfaceSubClass db ? bInterfaceProtocol db ? iInterface db ? ends struct endpoint_descr bLength db ? bDescriptorType db ? bEndpointAddress db ? bmAttributes db ? wMaxPacketSize dw ? bInterval db ? ends ; Mass storage protocol constants, USB layer REQUEST_GETMAXLUN = 0xFE ; get max lun REQUEST_BORESET = 0xFF ; bulk-only reset ; Mass storage protocol structures, USB layer ; Sent from host to device in the first stage of an operation. struct command_block_wrapper Signature dd ? ; the constant 'USBC' Tag dd ? ; identifies response with request Length dd ? ; length of data-transport phase Flags db ? ; one of CBW_FLAG_* CBW_FLAG_OUT = 0 CBW_FLAG_IN = 80h LUN db ? ; addressed unit CommandLength db ? ; the length of the following field Command rb 16 ends ; Sent from device to host in the last stage of an operation. struct command_status_wrapper Signature dd ? ; the constant 'USBS' Tag dd ? ; identifies response with request LengthRest dd ? ; .Length - (size of data which were transferred) Status db ? ; one of CSW_STATUS_* CSW_STATUS_OK = 0 CSW_STATUS_FAIL = 1 CSW_STATUS_FATAL = 2 ends ; Constants of SCSI layer SCSI_REQUEST_SENSE = 3 SCSI_INQUIRY = 12h SCSI_READ_CAPACITY = 25h SCSI_READ10 = 28h SCSI_WRITE10 = 2Ah ; Result of SCSI REQUEST SENSE command. SENSE_UNKNOWN = 0 SENSE_RECOVERED_ERROR = 1 SENSE_NOT_READY = 2 SENSE_MEDIUM_ERROR = 3 SENSE_HARDWARE_ERROR = 4 SENSE_ILLEGAL_REQUEST = 5 SENSE_UNIT_ATTENTION = 6 SENSE_DATA_PROTECT = 7 SENSE_BLANK_CHECK = 8 ; 9 is vendor-specific SENSE_COPY_ABORTED = 10 SENSE_ABORTED_COMMAND = 11 SENSE_EQUAL = 12 SENSE_VOLUME_OVERFLOW = 13 SENSE_MISCOMPARE = 14 ; 15 is reserved ; Structures of SCSI layer ; Result of SCSI INQUIRY request. struct inquiry_data PeripheralDevice db ? ; lower 5 bits are PeripheralDeviceType ; upper 3 bits are PeripheralQualifier RemovableMedium db ? ; upper bit is RemovableMedium ; other bits are for compatibility Version db ? ; lower 3 bits are ANSI-Approved version ; next 3 bits are ECMA version ; upper 2 bits are ISO version ResponseDataFormat db ? ; lower 4 bits are ResponseDataFormat ; bit 6 is TrmIOP ; bit 7 is AENC AdditionalLength db ? dw ? ; reserved Flags db ? VendorID rb 8 ; vendor ID, big-endian ProductID rb 16 ; product ID, big-endian ProductRevBE dd ? ; product revision, big-endian ends struct sense_data ErrorCode db ? ; lower 7 bits are error code: ; 70h = current error, ; 71h = deferred error ; upper bit is InformationValid SegmentNumber db ? ; number of segment descriptor ; for commands COPY [+VERIFY], COMPARE SenseKey db ? ; bits 0-3 are one of SENSE_* ; bit 4 is reserved ; bit 5 is IncorrectLengthIndicator ; bits 6 and 7 are used by ; sequential-access devices Information dd ? ; command-specific AdditionalLength db ? ; length of data starting here CommandInformation dd ? ; command-specific AdditionalSenseCode db ? ; \ more detailed error code AdditionalSenseQual db ? ; / standard has a large table of them FRUCode db ? ; which part of device has failed ; (device-specific, not regulated) SenseKeySpecific rb 3 ; depends on SenseKey ends ; Device data ; USB Mass storage device has one or more logical units, identified by LUN, ; logical unit number. The highest value of LUN, that is, number of units ; minus 1, can be obtained via control request Get Max LUN. struct usb_device_data ConfigPipe dd ? ; configuration pipe OutPipe dd ? ; pipe for OUT bulk endpoint InPipe dd ? ; pipe for IN bulk endpoint MaxLUN dd ? ; maximum Logical Unit Number LogicalDevices dd ? ; pointer to array of usb_unit_data ; 1 for a connected USB device, 1 for each disk device ; the structure can be freed when .NumReferences decreases to zero NumReferences dd ? ; number of references ConfigRequest rb 8 ; buffer for configuration requests LengthRest dd ? ; Length - (size of data which were transferred) ; All requests to a given device are serialized, ; only one request to a given device can be processed at a time. ; The current request and all pending requests are organized in the following ; queue, the head being the current request. ; NB: the queue must be device-wide due to the protocol: ; data stage is not tagged (unlike command_*_wrapper), so the only way to know ; what request the data are associated with is to guarantee that only one ; request is processing at the time. RequestsQueue rd 2 QueueLock rd 3 ; protects .RequestsQueue InquiryData inquiry_data ; information about device ; data for the current request Command command_block_wrapper DeviceDisconnected db ? Status command_status_wrapper Sense sense_data ends ; Information about one logical device. struct usb_unit_data Parent dd ? ; pointer to parent usb_device_data LUN db ? ; index in usb_device_data.LogicalDevices array DiskIndex db ? ; for name "usbhd" MediaPresent db ? db ? ; alignment DiskDevice dd ? ; handle of disk device or NULL SectorSize dd ? ; sector size ; For some devices, the first request to the medium fails with 'unit not ready'. ; When the code sees this status, it retries the command several times. ; Two following variables track the retry count and total time for those; ; total time is currently used only for debug output. UnitReadyAttempts dd ? TimerTicks dd ? ends ; This is the structure for items in the queue usb_device_data.RequestsQueue. struct request_queue_item Next dd ? ; next item in the queue Prev dd ? ; prev item in the queue ReqBuilder dd ? ; procedure to fill command_block_wrapper Buffer dd ? ; input or output data ; (length is command_block_wrapper.Length) Callback dd ? ; procedure to call in the end of transfer UserData dd ? ; passed as-is to .Callback ; There are 3 possible stages of any request, one of them optional: ; command stage (host sends command_block_wrapper to device), ; optional data stage, ; status stage (device sends command_status_wrapper to host). ; Also, if a request fails, the code queues additional request ; SCSI_REQUEST_SENSE; sense_data from SCSI_REQUEST_SENSE ; contains some information about the error. Stage db ? ends section '.flat' code readable writable executable include '../proc32.inc' include '../peimport.inc' include '../fdo.inc' include '../macros.inc' ; The start procedure. proc START virtual at esp dd ? ; return address .reason dd ? ; DRV_ENTRY or DRV_EXIT .cmdline dd ? end virtual ; 1. Test whether the procedure is called with the argument DRV_ENTRY. ; If not, return 0. xor eax, eax ; initialize return value cmp [.reason], 1 ; compare the argument jnz .nothing ; 2. Initialize: we have one global mutex. mov ecx, free_numbers_lock invoke MutexInit ; 3. Register self as a USB driver. ; The name is my_driver = 'usbstor'; IOCTL interface is not supported; ; usb_functions is an offset of a structure with callback functions. invoke RegUSBDriver, my_driver, 0, usb_functions ; 4. Return the returned value of RegUSBDriver. .nothing: ret endp ; Helper procedures to work with requests queue. ; Add a request to the queue. Stdcall with 5 arguments. proc queue_request push ebx esi virtual at esp rd 2 ; saved registers dd ? ; return address .device dd ? ; pointer to usb_device_data .ReqBuilder dd ? ; request_queue_item.ReqBuilder .Buffer dd ? ; request_queue_item.Buffer .Callback dd ? ; request_queue_item.Callback .UserData dd ? ; request_queue_item.UserData end virtual ; 1. Allocate the memory for the request description. movi eax, sizeof.request_queue_item invoke Kmalloc test eax, eax jnz @f mov esi, nomemory invoke SysMsgBoardStr pop esi ebx ret 20 @@: ; 2. Fill user-provided parts of the request description. push edi xchg eax, ebx lea esi, [.ReqBuilder+4] lea edi, [ebx+request_queue_item.ReqBuilder] movsd ; ReqBuilder movsd ; Buffer movsd ; Callback movsd ; UserData pop edi ; 3. Set stage to zero: not started. mov [ebx+request_queue_item.Stage], 0 ; 4. Lock the queue. mov esi, [.device] lea ecx, [esi+usb_device_data.QueueLock] invoke MutexLock ; 5. Insert the request to the tail of the queue. add esi, usb_device_data.RequestsQueue mov edx, [esi+request_queue_item.Prev] mov [ebx+request_queue_item.Next], esi mov [ebx+request_queue_item.Prev], edx mov [edx+request_queue_item.Next], ebx mov [esi+request_queue_item.Prev], ebx ; 6. Test whether the queue was empty ; and the request should be started immediately. cmp [esi+request_queue_item.Next], ebx jnz .unlock ; 8. If the step 6 shows that the request is the first in the queue, ; start it. sub esi, usb_device_data.RequestsQueue call setup_request jmp .nothing .unlock: invoke MutexUnlock ; 9. Return. .nothing: pop esi ebx ret 20 endp ; The current request is completed. Call the callback, ; remove the request from the queue, start the next ; request if there is one. ; esi points to usb_device_data proc complete_request ; 1. Print common debug messages on fails. if DEBUG cmp [esi+usb_device_data.Status.Status], CSW_STATUS_FAIL jb .normal jz .fail DEBUGF 1, 'K : Fatal error during execution of command %x\n', [esi+usb_device_data.Command.Command]:2 jmp .normal .fail: DEBUGF 1, 'K : Command %x failed\n', [esi+usb_device_data.Command.Command]:2 .normal: end if ; 2. Get the current request. mov ebx, [esi+usb_device_data.RequestsQueue+request_queue_item.Next] ; 3. Call the callback. stdcall [ebx+request_queue_item.Callback], esi, [ebx+request_queue_item.UserData] ; 4. Lock the queue. lea ecx, [esi+usb_device_data.QueueLock] invoke MutexLock ; 5. Remove the request. lea edx, [esi+usb_device_data.RequestsQueue] mov eax, [ebx+request_queue_item.Next] mov [eax+request_queue_item.Prev], edx mov [edx+request_queue_item.Next], eax ; 6. Free the request memory. push eax edx xchg eax, ebx invoke Kfree pop edx ebx ; 7. If there is a next request, start processing. cmp ebx, edx jnz setup_request ; 8. Unlock the queue and return. lea ecx, [esi+usb_device_data.QueueLock] invoke MutexUnlock ret endp ; Start processing the request. Called either by queue_request ; or when the previous request has been processed. ; Do not call directly, use queue_request. ; Must be called when queue is locked; unlocks the queue when returns. proc setup_request xor eax, eax ; 1. If DeviceDisconnected has been run, then all handles of pipes ; are invalid, so we must fail immediately. ; (That is why this function needs the locked queue: this ; guarantee that either DeviceDisconnected has been already run, or ; DeviceDisconnected will not return before the queue is unlocked.) cmp [esi+usb_device_data.DeviceDisconnected], al jnz .fatal ; 2. If the previous command has encountered a fatal error, ; perform reset recovery. cmp [esi+usb_device_data.Status.Status], CSW_STATUS_FATAL jb .norecovery ; 2a. Send Bulk-Only Mass Storage Reset command to config pipe. lea edx, [esi+usb_device_data.ConfigRequest] mov word [edx], (REQUEST_BORESET shl 8) + 21h ; class request mov word [edx+6], ax ; length = 0 invoke USBControlTransferAsync, [esi+usb_device_data.ConfigPipe], edx, eax, eax, recovery_callback1, esi, eax ; 2b. Fail here = fatal error. test eax, eax jz .fatal ; 2c. Otherwise, unlock the queue and return. recovery_callback1 will continue processing. .unlock_return: lea ecx, [esi+usb_device_data.QueueLock] invoke MutexUnlock ret .norecovery: ; 3. Send the command. Fail (no memory or device disconnected) = fatal error. ; Otherwise, go to 2c. call request_stage1 test eax, eax jnz .unlock_return .fatal: ; 4. Fatal error. Set status = FATAL, unlock the queue, complete the request. mov [esi+usb_device_data.Status.Status], CSW_STATUS_FATAL lea ecx, [esi+usb_device_data.QueueLock] invoke MutexUnlock jmp complete_request endp ; Initiate USB transfer for the first stage of a request (send command). proc request_stage1 mov ebx, [esi+usb_device_data.RequestsQueue+request_queue_item.Next] ; 1. Set the stage to 1 = command stage. inc [ebx+request_queue_item.Stage] ; 2. Generate the command. Zero-initialize and use the caller-provided proc. lea edx, [esi+usb_device_data.Command] xor eax, eax mov [edx+command_block_wrapper.CommandLength], 12 mov dword [edx+command_block_wrapper.Command], eax mov dword [edx+command_block_wrapper.Command+4], eax mov dword [edx+command_block_wrapper.Command+8], eax mov dword [edx+command_block_wrapper.Command+12], eax inc [edx+command_block_wrapper.Tag] stdcall [ebx+request_queue_item.ReqBuilder], edx, [ebx+request_queue_item.UserData] ; 4. Initiate USB transfer. lea edx, [esi+usb_device_data.Command] if DUMP_PACKETS DEBUGF 1,'K : USBSTOR out:' mov eax, edx mov ecx, sizeof.command_block_wrapper call debug_dump DEBUGF 1,'\n' end if invoke USBNormalTransferAsync, [esi+usb_device_data.OutPipe], edx, sizeof.command_block_wrapper, request_callback1, esi, 0 test eax, eax jz .nothing ; 5. If the next stage is data stage in the same direction, enqueue it here. cmp [esi+usb_device_data.Command.Flags], 0 js .nothing cmp [esi+usb_device_data.Command.Length], 0 jz .nothing mov edx, [esi+usb_device_data.RequestsQueue+request_queue_item.Next] if DUMP_PACKETS DEBUGF 1,'K : USBSTOR out:' mov eax, [edx+request_queue_item.Buffer] mov ecx, [esi+usb_device_data.Command.Length] call debug_dump DEBUGF 1,'\n' end if invoke USBNormalTransferAsync, [esi+usb_device_data.OutPipe], [edx+request_queue_item.Buffer], [esi+usb_device_data.Command.Length], request_callback2, esi, 0 .nothing: ret endp if DUMP_PACKETS proc debug_dump test ecx, ecx jz .done .loop: test ecx, 0Fh jnz @f DEBUGF 1,'\nK :' @@: DEBUGF 1,' %x',[eax]:2 inc eax dec ecx jnz .loop .done: ret endp end if ; Called when the Reset command is completed, ; either successfully or not. proc recovery_callback1 virtual at esp dd ? ; return address .pipe dd ? .status dd ? .buffer dd ? .length dd ? .calldata dd ? end virtual cmp [.status], 0 jnz .error ; todo: reset pipes push ebx esi mov esi, [.calldata+8] call request_stage1 pop esi ebx test eax, eax jz .error ret 20 .error: DEBUGF 1, 'K : error %d while resetting', [.status+24h] jmp request_callback1.common_error endp ; Called when the first stage of request is completed, ; either successfully or not. proc request_callback1 virtual at esp dd ? ; return address .pipe dd ? .status dd ? .buffer dd ? .length dd ? .calldata dd ? end virtual ; 1. Initialize. mov ecx, [.calldata] mov eax, [.status] ; 2. Test for error. test eax, eax jnz .error ; No error. ; 3. Increment the stage. mov edx, [ecx+usb_device_data.RequestsQueue+request_queue_item.Next] inc [edx+request_queue_item.Stage] ; 4. Check whether we need to send the data. ; 4a. If there is no data, skip this stage. cmp [ecx+usb_device_data.Command.Length], 0 jz ..request_get_status ; 4b. If data were enqueued in the first stage, do nothing, wait for request_callback2. cmp [ecx+usb_device_data.Command.Flags], 0 jns .nothing ; 5. Initiate USB transfer. If this fails, go to the error handler. invoke USBNormalTransferAsync, [ecx+usb_device_data.InPipe], [edx+request_queue_item.Buffer], [ecx+usb_device_data.Command.Length], request_callback2, ecx, 0 test eax, eax jz .error ; 6. The status stage goes to the same direction, enqueue it now. mov ecx, [.calldata] jmp ..enqueue_status .nothing: ret 20 .error: ; Error. ; 7. Print debug message and complete the request as failed. DEBUGF 1,'K : error %d after %d bytes in request stage\n',eax,[.length+24h] ; If device is disconnected and data stage is enqueued, do nothing; ; data stage callback will do everything. cmp eax, 16 jnz .common_error cmp [ecx+usb_device_data.Command.Flags], 0 js .common_error cmp [ecx+usb_device_data.Command.Length], 0 jz .common_error ret 20 .common_error: ; TODO: add recovery after STALL mov ecx, [.calldata] mov [ecx+usb_device_data.Status.Status], CSW_STATUS_FATAL push ebx esi mov esi, ecx call complete_request pop esi ebx ret 20 endp ; Called when the second stage of request is completed, ; either successfully or not. proc request_callback2 virtual at esp dd ? ; return address .pipe dd ? .status dd ? .buffer dd ? .length dd ? .calldata dd ? end virtual if DUMP_PACKETS mov eax, [.calldata] mov eax, [eax+usb_device_data.InPipe] cmp [.pipe], eax jnz @f DEBUGF 1,'K : USBSTOR in:' push eax ecx mov eax, [.buffer+8] mov ecx, [.length+8] call debug_dump pop ecx eax DEBUGF 1,'\n' @@: end if ; 1. Initialize. mov ecx, [.calldata] mov eax, [.status] ; 2. Test for error. test eax, eax jnz .error ; No error. ; If the previous stage was in same direction, do nothing; status request is already enqueued. cmp [ecx+usb_device_data.Command.Flags], 0 js .nothing ..request_get_status: ; 3. Increment the stage. mov edx, [ecx+usb_device_data.RequestsQueue+request_queue_item.Next] inc [edx+request_queue_item.Stage] ; 4. Initiate USB transfer. If this fails, go to the error handler. ..enqueue_status: lea edx, [ecx+usb_device_data.Status] invoke USBNormalTransferAsync, [ecx+usb_device_data.InPipe], edx, sizeof.command_status_wrapper, request_callback3, ecx, 0 test eax, eax jz .error .nothing: ret 20 .error: ; Error. ; 5. Print debug message and complete the request as failed. DEBUGF 1,'K : error %d after %d bytes in data stage\n',eax,[.length+24h] ; If device is disconnected and data stage is enqueued, do nothing; ; status stage callback will do everything. cmp [ecx+usb_device_data.Command.Flags], 0 js .nothing jmp request_callback1.common_error endp ; Called when the third stage of request is completed, ; either successfully or not. proc request_callback3 virtual at esp dd ? ; return address .pipe dd ? .status dd ? .buffer dd ? .length dd ? .calldata dd ? end virtual if DUMP_PACKETS DEBUGF 1,'K : USBSTOR in:' mov eax, [.buffer] mov ecx, [.length] call debug_dump DEBUGF 1,'\n' end if ; 1. Initialize. mov eax, [.status] ; 2. Test for error. test eax, eax jnz .transfer_error ; Transfer is OK. ; 3. Validate the status. Invalid status = fatal error. push ebx esi mov esi, [.calldata+8] mov ebx, [esi+usb_device_data.RequestsQueue+request_queue_item.Next] cmp [esi+usb_device_data.Status.Signature], 'USBS' jnz .invalid mov eax, [esi+usb_device_data.Command.Tag] cmp [esi+usb_device_data.Status.Tag], eax jnz .invalid cmp [esi+usb_device_data.Status.Status], CSW_STATUS_FATAL ja .invalid ; 4. The status block is valid. Check the status code. jz .complete ; 5. If this command was not REQUEST_SENSE, copy status data to safe place. ; Otherwise, the original command has failed, so restore the fail status. cmp byte [esi+usb_device_data.Command.Command], SCSI_REQUEST_SENSE jz .request_sense mov eax, [esi+usb_device_data.Status.LengthRest] mov [esi+usb_device_data.LengthRest], eax cmp [esi+usb_device_data.Status.Status], CSW_STATUS_FAIL jz .fail .complete: call complete_request .nothing: pop esi ebx ret 20 .request_sense: mov [esi+usb_device_data.Status.Status], CSW_STATUS_FAIL jmp .complete .invalid: ; 6. Invalid status block. Say error, set status to fatal and complete request. push esi mov esi, invresponse invoke SysMsgBoardStr pop esi mov [esi+usb_device_data.Status.Status], CSW_STATUS_FATAL jmp .complete .fail: ; 7. The command has failed. ; If this command was not REQUEST_SENSE, schedule the REQUEST_SENSE command ; to determine the reason of fail. Otherwise, assume that there is no error data. cmp [esi+usb_device_data.Command.Command], SCSI_REQUEST_SENSE jz .fail_request_sense mov [ebx+request_queue_item.ReqBuilder], request_sense_req lea eax, [esi+usb_device_data.Sense] mov [ebx+request_queue_item.Buffer], eax call request_stage1 test eax, eax jnz .nothing .fail_request_sense: DEBUGF 1,'K : fail during REQUEST SENSE\n' mov byte [esi+usb_device_data.Sense], 0 jmp .complete .transfer_error: ; TODO: add recovery after STALL DEBUGF 1,'K : error %d after %d bytes in status stage\n',eax,[.length+24h] jmp request_callback1.common_error endp ; Builder for SCSI_REQUEST_SENSE request. ; edx = first argument = pointer to usb_device_data.Command, ; second argument = custom data given to queue_request (ignored). proc request_sense_req mov [edx+command_block_wrapper.Length], sizeof.sense_data mov [edx+command_block_wrapper.Flags], CBW_FLAG_IN mov byte [edx+command_block_wrapper.Command+0], SCSI_REQUEST_SENSE mov byte [edx+command_block_wrapper.Command+4], sizeof.sense_data ret 8 endp ; This procedure is called when new mass-storage device is detected. ; It initializes the device. ; Technically, initialization implies sending several USB queries, ; so it is split in several procedures. The first is AddDevice, ; other are callbacks which will be called at some time in the future, ; when the device will respond. ; The general scheme: ; * AddDevice parses descriptors, opens pipes; if everything is ok, ; AddDevice sends REQUEST_GETMAXLUN with callback known_lun_callback; ; * known_lun_callback allocates memory for LogicalDevices and sends ; SCSI_TEST_UNIT_READY to all logical devices with test_unit_ready_callback; ; * test_unit_ready_callback checks whether the unit is ready; ; if not, it repeats the same request several times; ; if ok or there were too many attempts, it sends SCSI_INQUIRY with ; callback inquiry_callback; ; * inquiry_callback checks that a logical device is a block device ; and the unit was ready; if so, it notifies the kernel about new disk device. proc AddDevice push ebx esi virtual at esp rd 2 ; saved registers ebx, esi dd ? ; return address .pipe0 dd ? ; handle of the config pipe .config dd ? ; pointer to config_descr .interface dd ? ; pointer to interface_descr end virtual ; 1. Check device type. Currently only SCSI-command-set Bulk-only devices ; are supported. ; 1a. Get the subclass and the protocol. Since bInterfaceSubClass and ; bInterfaceProtocol are subsequent in interface_descr, just one ; memory reference is used for both. mov esi, [.interface] xor ebx, ebx mov cx, word [esi+interface_descr.bInterfaceSubClass] ; 1b. For Mass-storage SCSI-command-set Bulk-only devices subclass must be 6 ; and protocol must be 50h. Check. cmp cx, 0x5006 jz .known ; There are devices with subclass 5 which use the same protocol 50h. ; The difference is not important for the code except for this test, ; so allow them to proceed also. cmp cx, 0x5005 jz .known ; 1c. If the device is unknown, print a message and go to 11c. mov esi, unkdevice invoke SysMsgBoardStr jmp .nothing ; 1d. If the device uses known command set, print a message and continue ; configuring. .known: push esi mov esi, okdevice invoke SysMsgBoardStr pop esi ; 2. Allocate memory for internal device data. ; 2a. Call the kernel. mov eax, sizeof.usb_device_data invoke Kmalloc ; 2b. Check return value. test eax, eax jnz @f ; 2c. If failed, say a message and go to 11c. mov esi, nomemory invoke SysMsgBoardStr jmp .nothing @@: ; 2d. If succeeded, zero the contents and continue configuring. xchg ebx, eax ; ebx will point to usb_device_data xor eax, eax mov [ebx+usb_device_data.OutPipe], eax mov [ebx+usb_device_data.InPipe], eax mov [ebx+usb_device_data.MaxLUN], eax mov [ebx+usb_device_data.LogicalDevices], eax mov dword [ebx+usb_device_data.ConfigRequest], eax mov dword [ebx+usb_device_data.ConfigRequest+4], eax mov [ebx+usb_device_data.Status.Status], al mov [ebx+usb_device_data.DeviceDisconnected], al ; 2e. There is one reference: a connected USB device. inc eax mov [ebx+usb_device_data.NumReferences], eax ; 2f. Save handle of configuration pipe for reset recovery. mov eax, [.pipe0] mov [ebx+usb_device_data.ConfigPipe], eax ; 2g. Save the interface number for configuration requests. mov al, [esi+interface_descr.bInterfaceNumber] mov [ebx+usb_device_data.ConfigRequest+4], al ; 2h. Initialize common fields in command wrapper. mov [ebx+usb_device_data.Command.Signature], 'USBC' mov [ebx+usb_device_data.Command.Tag], 'xxxx' ; 2i. Initialize requests queue. lea eax, [ebx+usb_device_data.RequestsQueue] mov [eax+request_queue_item.Next], eax mov [eax+request_queue_item.Prev], eax lea ecx, [ebx+usb_device_data.QueueLock] invoke MutexInit ; Bulk-only mass storage devices use one OUT bulk endpoint for sending ; command/data and one IN bulk endpoint for receiving data/status. ; Look for those endpoints. ; 3. Get the upper bound of all descriptors' data. mov edx, [.config] ; configuration descriptor movzx ecx, [edx+config_descr.wTotalLength] add edx, ecx ; 4. Loop over all descriptors until ; either end-of-data reached - this is fail ; or interface descriptor found - this is fail, all further data ; correspond to that interface ; or both endpoint descriptors found. ; 4a. Loop start: esi points to the interface descriptor, .lookep: ; 4b. Get next descriptor. movzx ecx, byte [esi] ; the first byte of all descriptors is length add esi, ecx ; 4c. Check that at least two bytes are readable. The opposite is an error. inc esi cmp esi, edx jae .errorep dec esi ; 4d. Check that this descriptor is not interface descriptor. The opposite is ; an error. cmp byte [esi+endpoint_descr.bDescriptorType], INTERFACE_DESCR_TYPE jz .errorep ; 4e. Test whether this descriptor is an endpoint descriptor. If not, continue ; the loop. cmp byte [esi+endpoint_descr.bDescriptorType], ENDPOINT_DESCR_TYPE jnz .lookep ; 5. Check that the descriptor contains all required data and all data are ; readable. The opposite is an error. cmp byte [esi+endpoint_descr.bLength], sizeof.endpoint_descr jb .errorep lea ecx, [esi+sizeof.endpoint_descr] cmp ecx, edx ja .errorep ; 6. Check that the endpoint is bulk endpoint. The opposite is an error. mov cl, [esi+endpoint_descr.bmAttributes] and cl, 3 cmp cl, BULK_PIPE jnz .errorep ; 7. Get the direction of this endpoint. movzx ecx, [esi+endpoint_descr.bEndpointAddress] shr ecx, 7 ; 8. Test whether a pipe for this direction is already opened. If so, continue ; the loop. cmp [ebx+usb_device_data.OutPipe+ecx*4], 0 jnz .lookep ; 9. Open pipe for this endpoint. ; 9a. Save registers. push ecx edx ; 9b. Load parameters from the descriptor. movzx ecx, [esi+endpoint_descr.bEndpointAddress] movzx edx, [esi+endpoint_descr.wMaxPacketSize] movzx eax, [esi+endpoint_descr.bInterval] ; not used for USB1, may be important for USB2 ; 9c. Call the kernel. invoke USBOpenPipe, [ebx+usb_device_data.ConfigPipe], ecx, edx, BULK_PIPE, eax ; 9d. Restore registers. pop edx ecx ; 9e. Check result. If failed, go to 11b. test eax, eax jz .free ; 9f. Save result. mov [ebx+usb_device_data.OutPipe+ecx*4], eax ; 10. Test whether the second pipe is already opened. If not, continue loop. xor ecx, 1 cmp [ebx+usb_device_data.OutPipe+ecx*4], 0 jz .lookep jmp .created ; 11. An error occured during processing endpoint descriptor. .errorep: ; 11a. Print a message. DEBUGF 1,'K : error: invalid endpoint descriptor\n' .free: ; 11b. Free the allocated usb_device_data. xchg eax, ebx invoke Kfree .nothing: ; 11c. Return an error. xor eax, eax jmp .return .created: ; 12. Pipes are opened. Send GetMaxLUN control request. lea eax, [ebx+usb_device_data.ConfigRequest] mov byte [eax], 0A1h ; class request from interface mov byte [eax+1], REQUEST_GETMAXLUN mov byte [eax+6], 1 ; transfer 1 byte lea ecx, [ebx+usb_device_data.MaxLUN] if DUMP_PACKETS DEBUGF 1,'K : GETMAXLUN: %x %x %x %x %x %x %x %x\n',[eax]:2,[eax+1]:2,[eax+2]:2,[eax+3]:2,[eax+4]:2,[eax+5]:2,[eax+6]:2,[eax+7]:2 end if invoke USBControlTransferAsync, [ebx+usb_device_data.ConfigPipe], eax, ecx, 1, known_lun_callback, ebx, 0 ; 13. Return with pointer to device data as returned value. xchg eax, ebx .return: pop esi ebx ret 12 endp ; This function is called when REQUEST_GETMAXLUN is done, ; either successful or unsuccessful. proc known_lun_callback push ebx esi virtual at esp rd 2 ; saved registers dd ? ; return address .pipe dd ? .status dd ? .buffer dd ? .length dd ? .calldata dd ? end virtual ; 1. Check the status. If the request failed, assume that MaxLUN is zero. mov ebx, [.calldata] mov eax, [.status] test eax, eax jz @f DEBUGF 1, 'K : GETMAXLUN failed with status %d, assuming zero\n', eax mov [ebx+usb_device_data.MaxLUN], 0 @@: ; 2. Allocate the memory for logical devices. mov eax, [ebx+usb_device_data.MaxLUN] inc eax DEBUGF 1,'K : %d logical unit(s)\n',eax imul eax, sizeof.usb_unit_data push ebx invoke Kmalloc pop ebx ; If failed, print a message and do nothing. test eax, eax jnz @f mov esi, nomemory invoke SysMsgBoardStr pop esi ebx ret 20 @@: mov [ebx+usb_device_data.LogicalDevices], eax ; 3. Initialize logical devices and initiate TEST_UNIT_READY request. xchg esi, eax xor ecx, ecx .looplun: mov [esi+usb_unit_data.Parent], ebx mov [esi+usb_unit_data.LUN], cl xor eax, eax mov [esi+usb_unit_data.MediaPresent], al mov [esi+usb_unit_data.DiskDevice], eax mov [esi+usb_unit_data.SectorSize], eax mov [esi+usb_unit_data.UnitReadyAttempts], eax push ecx invoke GetTimerTicks mov [esi+usb_unit_data.TimerTicks], eax stdcall queue_request, ebx, test_unit_ready_req, 0, test_unit_ready_callback, esi pop ecx inc ecx add esi, sizeof.usb_unit_data cmp ecx, [ebx+usb_device_data.MaxLUN] jbe .looplun ; 4. Return. pop esi ebx ret 20 endp ; Builder for SCSI INQUIRY request. ; edx = first argument = pointer to usb_device_data.Command, ; second argument = custom data given to queue_request. proc inquiry_req mov eax, [esp+8] mov al, [eax+usb_unit_data.LUN] mov [edx+command_block_wrapper.Length], sizeof.inquiry_data mov [edx+command_block_wrapper.Flags], CBW_FLAG_IN mov [edx+command_block_wrapper.LUN], al mov byte [edx+command_block_wrapper.Command+0], SCSI_INQUIRY mov byte [edx+command_block_wrapper.Command+4], sizeof.inquiry_data ret 8 endp ; Called when SCSI INQUIRY request is completed. proc inquiry_callback ; 1. Check the status. mov ecx, [esp+4] cmp [ecx+usb_device_data.Status.Status], CSW_STATUS_OK jnz .fail ; 2. The command has completed successfully. ; Print a message showing device type, ignore anything but block devices. mov al, [ecx+usb_device_data.InquiryData.PeripheralDevice] and al, 1Fh DEBUGF 1,'K : peripheral device type is %x\n',al test al, al jnz .nothing DEBUGF 1,'K : direct-access mass storage device detected\n' ; 3. We have found a new disk device. Increment number of references. lock inc [ecx+usb_device_data.NumReferences] ; Unfortunately, we are now in the context of the USB thread, ; so we can't notify the kernel immediately: it would try to do something ; with a new disk, those actions would be synchronous and would require ; waiting for results of USB requests, but we need to exit this callback ; to allow the USB thread to continue working and handling those requests. ; 4. Thus, create a temporary kernel thread which would do it. mov edx, [esp+8] push ebx ecx esi edi movi ebx, 1 mov ecx, new_disk_thread ; edx = parameter invoke CreateThread pop edi esi ecx ebx cmp eax, -1 jnz .nothing ; on error, reverse step 3 lock dec [ecx+usb_device_data.NumReferences] .nothing: ret 8 .fail: ; 4. The command has failed. Print a message and do nothing. push esi mov esi, inquiry_fail invoke SysMsgBoardStr pop esi ret 8 endp ; Builder for SCSI TEST_UNIT_READY request. ; edx = first argument = pointer to usb_device_data.Command, ; second argument = custom data given to queue_request. proc test_unit_ready_req mov eax, [esp+8] mov al, [eax+usb_unit_data.LUN] mov [edx+command_block_wrapper.Length], 0 mov [edx+command_block_wrapper.Flags], CBW_FLAG_IN mov [edx+command_block_wrapper.LUN], al ret 8 endp ; Called when SCSI TEST_UNIT_READY request is completed. proc test_unit_ready_callback virtual at esp dd ? ; return address .device dd ? .calldata dd ? end virtual ; 1. Check the status. mov ecx, [.device] mov edx, [.calldata] cmp [ecx+usb_device_data.Status.Status], CSW_STATUS_OK jnz .fail ; 2. The command has completed successfully, ; possibly after some repetitions. Print a debug message showing ; number and time of those. Remember that media is ready and go to 4. DEBUGF 1,'K : media is ready\n' invoke GetTimerTicks sub eax, [edx+usb_unit_data.TimerTicks] DEBUGF 1,'K : %d attempts, %d ticks\n',[edx+usb_unit_data.UnitReadyAttempts],eax inc [edx+usb_unit_data.MediaPresent] jmp .inquiry .fail: ; 3. The command has failed. ; Retry the same request up to 3 times with 10ms delay; ; if limit of retries is not reached, exit from the function. ; Otherwise, go to 4. inc [edx+usb_unit_data.UnitReadyAttempts] cmp [edx+usb_unit_data.UnitReadyAttempts], 3 jz @f push ecx edx esi movi esi, 10 invoke Sleep pop esi edx ecx stdcall queue_request, ecx, test_unit_ready_req, 0, test_unit_ready_callback, edx ret 8 @@: DEBUGF 1,'K : media not ready\n' .inquiry: ; 4. initiate INQUIRY request. lea eax, [ecx+usb_device_data.InquiryData] stdcall queue_request, ecx, inquiry_req, eax, inquiry_callback, edx ret 8 endp ; Temporary thread for initial actions with a new disk device. proc new_disk_thread sub esp, 32 virtual at esp .name rb 32 ; device name .param dd ? ; contents of edx at the moment of int 0x40/eax=51 dd ? ; stack segment end virtual ; We are ready to notify the kernel about a new disk device. mov esi, [.param] ; 1. Generate name. ; 1a. Find a free index. mov ecx, free_numbers_lock invoke MutexLock xor eax, eax @@: bsf edx, [free_numbers+eax] jnz @f add eax, 4 cmp eax, 4*4 jnz @b invoke MutexUnlock push esi mov esi, noindex invoke SysMsgBoardStr pop esi jmp .drop_reference @@: ; 1b. Mark the index as busy. btr [free_numbers+eax], edx lea eax, [eax*8+edx] push eax invoke MutexUnlock pop eax ; 1c. Generate a name of the form "usbhd" in the stack. mov dword [esp], 'usbh' lea edi, [esp+5] mov byte [edi-1], 'd' push eax push -'0' movi ecx, 10 @@: cdq div ecx push edx test eax, eax jnz @b @@: pop eax add al, '0' stosb jnz @b pop ecx mov edx, esp ; 3d. Store the index in usb_unit_data to free it later. mov [esi+usb_unit_data.DiskIndex], cl ; 4. Notify the kernel about a new disk. ; 4a. Add a disk. ; stdcall queue_request, ecx, read_capacity_req, eax, read_capacity_callback, eax invoke DiskAdd, disk_functions, edx, esi, 0 mov ebx, eax ; 4b. If it failed, release the index and do nothing. test eax, eax jz .free_index ; 4c. Notify the kernel that a media is present. invoke DiskMediaChanged, eax, 1 ; 5. Lock the requests queue, check that device is not disconnected, ; store the disk handle, unlock the requests queue. mov ecx, [esi+usb_unit_data.Parent] add ecx, usb_device_data.QueueLock invoke MutexLock cmp byte [ecx+usb_device_data.DeviceDisconnected-usb_device_data.QueueLock], 0 jnz .disconnected mov [esi+usb_unit_data.DiskDevice], ebx invoke MutexUnlock jmp .exit .disconnected: invoke MutexUnlock stdcall disk_close, ebx jmp .exit .free_index: mov ecx, free_numbers_lock invoke MutexLock movzx eax, [esi+usb_unit_data.DiskIndex] bts [free_numbers], eax invoke MutexUnlock .drop_reference: mov esi, [esi+usb_unit_data.Parent] lock dec [esi+usb_device_data.NumReferences] jnz .exit mov eax, [esi+usb_device_data.LogicalDevices] invoke Kfree xchg eax, esi invoke Kfree .exit: or eax, -1 int 0x40 endp ; This function is called when the device is disconnected. proc DeviceDisconnected push ebx esi virtual at esp rd 2 ; saved registers dd ? ; return address .device dd ? end virtual ; 1. Say a message. mov esi, disconnectmsg invoke SysMsgBoardStr ; 2. Lock the requests queue, set .DeviceDisconnected to 1, ; unlock the requests queue. ; Locking is required for synchronization with queue_request: ; all USB callbacks are executed in the same thread and are ; synchronized automatically, but queue_request can be running ; from any thread which wants to do something with a filesystem. ; Without locking, it would be possible that queue_request has ; been started, has checked that device is not yet disconnected, ; then DeviceDisconnected completes and all handles become invalid, ; then queue_request tries to use them. mov esi, [.device] lea ecx, [esi+usb_device_data.QueueLock] invoke MutexLock mov [esi+usb_device_data.DeviceDisconnected], 1 invoke MutexUnlock ; 3. Drop one reference to the structure and check whether ; that was the last reference. lock dec [esi+usb_device_data.NumReferences] jz .free ; 4. If not, there are some additional references due to disk devices; ; notify the kernel that those disks are deleted. ; Note that new disks cannot be added while we are looping here, ; because new_disk_thread checks for .DeviceDisconnected. mov ebx, [esi+usb_device_data.MaxLUN] mov esi, [esi+usb_device_data.LogicalDevices] inc ebx .diskdel: mov eax, [esi+usb_unit_data.DiskDevice] test eax, eax jz @f invoke DiskDel, eax @@: add esi, sizeof.usb_unit_data dec ebx jnz .diskdel ; In this case, some operations with those disks are still possible, ; so we can't do anything more now. disk_close will take care of the rest. .return: pop esi ebx ret 4 ; 5. If there are no disk devices, free all resources which were allocated. .free: mov eax, [esi+usb_device_data.LogicalDevices] test eax, eax jz @f invoke Kfree @@: xchg eax, esi invoke Kfree jmp .return endp ; Disk functions. DISK_STATUS_OK = 0 ; success DISK_STATUS_GENERAL_ERROR = -1; if no other code is suitable DISK_STATUS_INVALID_CALL = 1 ; invalid input parameters DISK_STATUS_NO_MEDIA = 2 ; no media present DISK_STATUS_END_OF_MEDIA = 3 ; end of media while reading/writing data ; Called when all operations with the given disk are done. proc disk_close push ebx esi virtual at esp rd 2 ; saved registers dd ? ; return address .userdata dd ? end virtual mov esi, [.userdata] mov ecx, free_numbers_lock invoke MutexLock movzx eax, [esi+usb_unit_data.DiskIndex] bts [free_numbers], eax invoke MutexUnlock mov esi, [esi+usb_unit_data.Parent] lock dec [esi+usb_device_data.NumReferences] jnz .nothing mov eax, [esi+usb_device_data.LogicalDevices] invoke Kfree xchg eax, esi invoke Kfree .nothing: pop esi ebx ret 4 endp ; Returns sector size, capacity and flags of the media. proc disk_querymedia stdcall uses ebx esi edi, \ userdata:dword, mediainfo:dword ; 1. Create event for waiting. xor esi, esi xor ecx, ecx invoke CreateEvent test eax, eax jz .generic_fail push eax push edx push ecx push 0 push 0 virtual at ebp-.localsize .locals: ; two following dwords are the output of READ_CAPACITY .LastLBABE dd ? .SectorSizeBE dd ? .Status dd ? ; two following dwords identify an event .event_code dd ? .event dd ? rd 3 ; saved registers .localsize = $ - .locals dd ? ; saved ebp dd ? ; return address .userdata dd ? .mediainfo dd ? end virtual ; 2. Initiate SCSI READ_CAPACITY request. mov eax, [userdata] mov ecx, [eax+usb_unit_data.Parent] mov edx, esp stdcall queue_request, ecx, read_capacity_req, edx, read_capacity_callback, edx ; 3. Wait for event. This destroys it. mov eax, [.event] mov ebx, [.event_code] invoke WaitEvent ; 4. Get the status and results. pop ecx bswap ecx ; .LastLBA pop edx bswap edx ; .SectorSize pop eax ; .Status ; 5. If the request has completed successfully, store results. test eax, eax jnz @f DEBUGF 1,'K : sector size is %d, last sector is %d\n',edx,ecx mov ebx, [mediainfo] mov [ebx], eax ; flags = 0 mov [ebx+4], edx ; sectorsize add ecx, 1 adc eax, 0 mov [ebx+8], ecx mov [ebx+12], eax ; capacity mov eax, [userdata] mov [eax+usb_unit_data.SectorSize], edx xor eax, eax @@: ; 6. Restore the stack and return. pop ecx pop ecx ret .generic_fail: or eax, -1 ret endp ; Builder for SCSI READ_CAPACITY request. ; edx = first argument = pointer to usb_device_data.Command, ; second argument = custom data given to queue_request, ; pointer to disk_querymedia.locals. proc read_capacity_req mov eax, [esp+8] mov eax, [eax+disk_querymedia.userdata-disk_querymedia.locals] mov al, [eax+usb_unit_data.LUN] mov [edx+command_block_wrapper.Length], 8 mov [edx+command_block_wrapper.Flags], CBW_FLAG_IN mov [edx+command_block_wrapper.LUN], al mov byte [edx+command_block_wrapper.Command+0], SCSI_READ_CAPACITY ret 8 endp ; Called when SCSI READ_CAPACITY request is completed. proc read_capacity_callback ; Transform the status to return value of disk_querymedia ; and set the event. mov ecx, [esp+4] xor eax, eax cmp [ecx+usb_device_data.Status.Status], al jz @f or eax, -1 @@: mov ecx, [esp+8] mov [ecx+disk_querymedia.Status-disk_querymedia.locals], eax push ebx esi edi mov eax, [ecx+disk_querymedia.event-disk_querymedia.locals] mov ebx, [ecx+disk_querymedia.event_code-disk_querymedia.locals] xor edx, edx xor esi, esi invoke RaiseEvent pop edi esi ebx ret 8 endp disk_write: mov al, SCSI_WRITE10 jmp disk_read_write disk_read: mov al, SCSI_READ10 ; Reads from the device or writes to the device. proc disk_read_write stdcall uses ebx esi edi, \ userdata:dword, buffer:dword, startsector:qword, numsectors:dword ; 1. Initialize. push eax ; .command mov eax, [userdata] mov eax, [eax+usb_unit_data.SectorSize] push eax ; .SectorSize push 0 ; .processed mov eax, [numsectors] mov eax, [eax] ; 2. The transfer length for SCSI_{READ,WRITE}10 commands can not be greater ; than 0xFFFF, so split the request to slices with <= 0xFFFF sectors. max_sectors_at_time = 0xFFFF .split: push eax ; .length_rest cmp eax, max_sectors_at_time jb @f mov eax, max_sectors_at_time @@: sub [esp], eax push eax ; .length_cur ; 3. startsector must fit in 32 bits, otherwise abort the request. cmp dword [startsector+4], 0 jnz .generic_fail ; 4. Create event for waiting. xor esi, esi xor ecx, ecx invoke CreateEvent test eax, eax jz .generic_fail push eax ; .event push edx ; .event_code push ecx ; .status virtual at ebp-.localsize .locals: .status dd ? .event_code dd ? .event dd ? .length_cur dd ? .length_rest dd ? .processed dd ? .SectorSize dd ? .command db ? rb 3 rd 3 ; saved registers .localsize = $ - .locals dd ? ; saved ebp dd ? ; return address .userdata dd ? .buffer dd ? .startsector dq ? .numsectors dd ? end virtual ; 5. Initiate SCSI READ10 or WRITE10 request. mov eax, [userdata] mov ecx, [eax+usb_unit_data.Parent] stdcall queue_request, ecx, read_write_req, [buffer], read_write_callback, esp ; 6. Wait for event. This destroys it. mov eax, [.event] mov ebx, [.event_code] invoke WaitEvent ; 7. Get the status. If the operation has failed, abort. pop eax ; .status pop ecx ecx ; cleanup .event_code, .event pop ecx ; .length_cur test eax, eax jnz .return ; 8. Otherwise, continue the loop started at step 2. add dword [startsector], ecx adc dword [startsector+4], eax imul ecx, [.SectorSize] add [buffer], ecx pop eax test eax, eax jnz .split push eax .return: ; 9. Restore the stack, store .processed to [numsectors], return. pop ecx ; .length_rest pop ecx ; .processed mov edx, [numsectors] mov [edx], ecx pop ecx ; .SectorSize pop ecx ; .command ret .generic_fail: or eax, -1 pop ecx ; .length_cur jmp .return endp ; Builder for SCSI READ10 or WRITE10 request. ; edx = first argument = pointer to usb_device_data.Command, ; second argument = custom data given to queue_request, ; pointer to disk_read_write.locals. proc read_write_req mov eax, [esp+8] mov ecx, [eax+disk_read_write.userdata-disk_read_write.locals] mov cl, [ecx+usb_unit_data.LUN] mov [edx+command_block_wrapper.LUN], cl mov ecx, [eax+disk_read_write.length_cur-disk_read_write.locals] imul ecx, [eax+disk_read_write.SectorSize-disk_read_write.locals] mov [edx+command_block_wrapper.Length], ecx mov cl, [eax+disk_read_write.command-disk_read_write.locals] mov [edx+command_block_wrapper.Flags], CBW_FLAG_OUT cmp cl, SCSI_READ10 jnz @f mov [edx+command_block_wrapper.Flags], CBW_FLAG_IN @@: mov byte [edx+command_block_wrapper.Command], cl mov ecx, dword [eax+disk_read_write.startsector-disk_read_write.locals] bswap ecx mov dword [edx+command_block_wrapper.Command+2], ecx mov ecx, [eax+disk_read_write.length_cur-disk_read_write.locals] xchg cl, ch mov word [edx+command_block_wrapper.Command+7], cx ret 8 endp ; Called when SCSI READ10 or WRITE10 request is completed. proc read_write_callback ; 1. Initialize. push ebx esi edi virtual at esp rd 3 ; saved registers dd ? ; return address .device dd ? .calldata dd ? end virtual mov ecx, [.device] mov esi, [.calldata] ; 2. Get the number of sectors which were read. ; If the status is OK or FAIL, the field .LengthRest is valid. ; Otherwise, it is invalid, so assume zero sectors. xor eax, eax cmp [ecx+usb_device_data.Status.Status], CSW_STATUS_FAIL ja .sectors_calculated mov eax, [ecx+usb_device_data.LengthRest] xor edx, edx div [esi+disk_read_write.SectorSize-disk_read_write.locals] test edx, edx jz @f inc eax @@: mov edx, eax mov eax, [esi+disk_read_write.length_cur-disk_read_write.locals] sub eax, edx jae .sectors_calculated xor eax, eax .sectors_calculated: ; 3. Increase the total number of processed sectors. add [esi+disk_read_write.processed-disk_read_write.locals], eax ; 4. Set status to OK if all sectors were read, to ERROR otherwise. cmp eax, [esi+disk_read_write.length_cur-disk_read_write.locals] setz al movzx eax, al dec eax mov [esi+disk_read_write.status-disk_read_write.locals], eax ; 5. Set the event. mov eax, [esi+disk_read_write.event-disk_read_write.locals] mov ebx, [esi+disk_read_write.event_code-disk_read_write.locals] xor edx, edx xor esi, esi invoke RaiseEvent ; 6. Return. pop edi esi ebx ret 8 endp ; strings my_driver db 'usbstor',0 disconnectmsg db 'K : USB mass storage device disconnected',13,10,0 nomemory db 'K : no memory',13,10,0 unkdevice db 'K : unknown mass storage device',13,10,0 okdevice db 'K : USB mass storage device detected',13,10,0 transfererror db 'K : USB transfer error, disabling mass storage',13,10,0 invresponse db 'K : invalid response from mass storage device',13,10,0 fatalerr db 'K : mass storage device reports fatal error',13,10,0 inquiry_fail db 'K : INQUIRY command failed',13,10,0 ;read_capacity_fail db 'K : READ CAPACITY command failed',13,10,0 ;read_fail db 'K : READ command failed',13,10,0 noindex db 'K : failed to generate disk name',13,10,0 align 4 ; Structure with callback functions. usb_functions: dd usb_functions_end - usb_functions dd AddDevice dd DeviceDisconnected usb_functions_end: disk_functions: dd disk_functions_end - disk_functions dd disk_close dd 0 ; closemedia dd disk_querymedia dd disk_read dd disk_write dd 0 ; flush dd 0 ; adjust_cache_size: use default cache disk_functions_end: data fixups end data free_numbers_lock rd 3 ; 128 devices should be enough for everybody free_numbers dd -1, -1, -1, -1 ; for DEBUGF macro include_debug_strings